We are seeing nas use near 100% cpu on our proxy hub and we are no longer get alarms from our third tier hubs.
This likely is related to a probe on the third tier hub generating a very high volume of alarms. Cross checking the alarm counts on the proxy and the third tier hub will generally show that the proxy has the same alarm but the total alarm count is much lower than at the third tier hub.
This would indicate that the proxy is unable to keep up with the quantity of alarms coming into it from the third tier hub. Check the third tier hub for he offending profile and turn it off. After doing this clear the alarm on both the hubs. It may take some time for these to flush out but you should see the nas probe on the proxy should return to a reasonable cpu utilization.
You will than want to determine what about the respective profile was causing such high alarming characteristics.